Suggest solver for gorgonia iris example

[c-bata]

(venv) $ ./bin/gorgonia_iris -dataset ./_examples/gorgonia_iris/iris.csv 
2020/04/20 03:27:27 [INFO] Trial finished: trialID=1 state=Complete evaluation=0.000000
2020/04/20 03:27:28 [INFO] Trial finished: trialID=2 state=Complete evaluation=0.886667
2020/04/20 03:27:28 [INFO] Trial finished: trialID=3 state=Complete evaluation=0.973333
2020/04/20 03:27:29 [INFO] Trial finished: trialID=4 state=Complete evaluation=0.426667
2020/04/20 03:27:30 [INFO] Trial finished: trialID=5 state=Complete evaluation=0.960000
2020/04/20 03:27:30 [INFO] Trial finished: trialID=6 state=Complete evaluation=0.973333
2020/04/20 03:27:31 [INFO] Trial finished: trialID=7 state=Complete evaluation=0.753333
2020/04/20 03:27:31 [INFO] Trial finished: trialID=8 state=Complete evaluation=0.973333
2020/04/20 03:27:32 [INFO] Trial finished: trialID=9 state=Complete evaluation=0.973333
2020/04/20 03:27:33 [INFO] Trial finished: trialID=10 state=Complete evaluation=0.973333
2020/04/20 03:27:33 [INFO] Trial finished: trialID=11 state=Complete evaluation=0.700000
2020/04/20 03:27:34 [INFO] Trial finished: trialID=12 state=Complete evaluation=0.973333
2020/04/20 03:27:35 [INFO] Trial finished: trialID=13 state=Complete evaluation=0.960000
2020/04/20 03:27:35 [INFO] Trial finished: trialID=14 state=Complete evaluation=0.000000
2020/04/20 03:27:36 [INFO] Trial finished: trialID=15 state=Complete evaluation=0.966667
2020/04/20 03:27:36 [INFO] Trial finished: trialID=16 state=Complete evaluation=0.613333
2020/04/20 03:27:37 [INFO] Trial finished: trialID=17 state=Complete evaluation=0.920000
2020/04/20 03:27:38 [INFO] Trial finished: trialID=18 state=Complete evaluation=0.973333
2020/04/20 03:27:39 [INFO] Trial finished: trialID=19 state=Complete evaluation=0.973333
2020/04/20 03:27:39 [INFO] Trial finished: trialID=20 state=Complete evaluation=0.973333
2020/04/20 03:27:40 [INFO] Trial finished: trialID=21 state=Complete evaluation=0.973333
2020/04/20 03:27:41 [INFO] Trial finished: trialID=22 state=Complete evaluation=0.973333
2020/04/20 03:27:41 [INFO] Trial finished: trialID=23 state=Complete evaluation=0.973333
2020/04/20 03:27:42 [INFO] Trial finished: trialID=24 state=Complete evaluation=0.973333
2020/04/20 03:27:43 [INFO] Trial finished: trialID=25 state=Complete evaluation=0.973333
2020/04/20 03:27:44 [INFO] Trial finished: trialID=26 state=Complete evaluation=0.973333
2020/04/20 03:27:45 [INFO] Trial finished: trialID=27 state=Complete evaluation=0.966667
2020/04/20 03:27:45 [INFO] Trial finished: trialID=28 state=Complete evaluation=0.973333
2020/04/20 03:27:46 [INFO] Trial finished: trialID=29 state=Complete evaluation=0.973333
2020/04/20 03:27:47 [INFO] Trial finished: trialID=30 state=Complete evaluation=0.966667
2020/04/20 03:27:48 [INFO] Trial finished: trialID=31 state=Complete evaluation=0.966667
2020/04/20 03:27:48 [INFO] Trial finished: trialID=32 state=Complete evaluation=0.973333
2020/04/20 03:27:49 [INFO] Trial finished: trialID=33 state=Complete evaluation=0.973333
2020/04/20 03:27:50 [INFO] Trial finished: trialID=34 state=Complete evaluation=0.973333
2020/04/20 03:27:51 [INFO] Trial finished: trialID=35 state=Complete evaluation=0.973333
2020/04/20 03:27:51 [INFO] Trial finished: trialID=36 state=Complete evaluation=0.973333
2020/04/20 03:27:52 [INFO] Trial finished: trialID=37 state=Complete evaluation=0.973333
2020/04/20 03:27:53 [INFO] Trial finished: trialID=38 state=Complete evaluation=0.973333
2020/04/20 03:27:54 [INFO] Trial finished: trialID=39 state=Complete evaluation=0.973333
2020/04/20 03:27:54 [INFO] Trial finished: trialID=40 state=Complete evaluation=0.973333
2020/04/20 03:27:55 [INFO] Trial finished: trialID=41 state=Complete evaluation=0.973333
2020/04/20 03:27:56 [INFO] Trial finished: trialID=42 state=Complete evaluation=0.973333
2020/04/20 03:27:56 [INFO] Trial finished: trialID=43 state=Complete evaluation=0.973333
2020/04/20 03:27:57 [INFO] Trial finished: trialID=44 state=Complete evaluation=0.973333
2020/04/20 03:27:58 [INFO] Trial finished: trialID=45 state=Complete evaluation=0.973333
2020/04/20 03:27:59 [INFO] Trial finished: trialID=46 state=Complete evaluation=0.973333
2020/04/20 03:27:59 [INFO] Trial finished: trialID=47 state=Complete evaluation=0.973333
2020/04/20 03:28:00 [INFO] Trial finished: trialID=48 state=Complete evaluation=0.973333
2020/04/20 03:28:01 [INFO] Trial finished: trialID=49 state=Complete evaluation=0.973333
2020/04/20 03:28:02 [INFO] Trial finished: trialID=50 state=Complete evaluation=0.966667
2020/04/20 03:28:02 Best evaluation=0.973333
2020/04/20 03:28:02 Solver: Vanilla
2020/04/20 03:28:02 Learning rate (vanilla): 0.004206